Free Space Path Loss Calculator

Pasternack's Free Space Path Loss Calculator calculates the loss (in dB) between two antennas where the gain, distance and frequency are known.

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Distance:

Frequency:

Transmitter Gain (dB):

Receiver Gain (dB):

Result:

Free Space Path Loss:

Free Space Path Loss (FSPL) calculations are often used to help predict RF signal strength in an antenna system. Loss increases with distance, so understanding the FSPL is an essential parameter for engineers dealing with RF communications systems.

**Note: All of our calculators allow SI prefix input. For example, if you wish to input "25000000", just type "25M" instead. See the quick-reference table below for all compatible SI prefixes.